using System;

using System.Collections.Concurrent;

using System.Collections.Generic;

using System.Threading.Tasks;

public class Program

{

    public static void Main()

    {

        int Function1(int input)

            {

                return 10 * input;

            }

            int Function2(int input)

            {

                return 20 * input;

            }

            int Function3(int input)

            {

                return 30 * input;

            }

            List<int> list = new List<int> { 2, 3 };

            Dictionary<int, Func<int, int>> actions = new Dictionary<int, Func<int, int>>()

            {

               {1, (arg) => Function1(arg)},

               {2, (arg) => Function2(arg)},

               {3, (arg) => Function3(arg)}

            };

            var bag = new ConcurrentBag<int>();

​

            Parallel.ForEach(actions,  action => { 

                if(action.Key == 2 || action.Key == 3)

                {

                    bag.Add(action.Value.Invoke(3));

                }                

            });

​

            foreach(var number in bag)

            {

                Console.WriteLine(number);

            }

    }

}